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Communities Mobilizing for Change on Alcohol : Initial
Outcomes from a Randomized Trial
A . C. W agen aar, PhD , D . M . M urray, PhD , J. P. G ehan , M P A , M A , M . W olfson , PhD ,
J. F orster , P hD , T . L . Toorney, P hD , C. L. P erry , PhD , R. Jon es-W eb b , D rP h
U niversity o f M innesota, School o f Public H ealth , D ivision o f E p idem io logy , 1300 S. 2nd Street, S uite 300, M inneapolis, M N 55454-1015 U SA
T he C om m unities M obiliz ing fo r C hange on A lcohol (C M C A ) project w as a com m unity -
o rgan iz ing effo rt to reduce underage alcohol use and resu lting p roblem s, such as traffic
crashes, using a theory-based process o f com m unity activation . O bjectives o f th is random ized
com m unity trial include; (1) reducing the availability o f alcohol to youth under age 21 (the
legal age fo r d rink ing in the U nited S tates), (2) reducing alcohol consum ption am ong youth,
and (3) reducing injury and o ther health and social prob lem s associated w ith alcohol use
am ong young people. W e hypothesized that reductions in underage drink ing w ould result
from changes in com m unity - and institu tional-level policies and practices, w ith consequent
reductions in in ju ry m orb id ity and o ther social and health prob lem s associated w ith underage
d rinking. F urther, w e expect those changes w ill con tinue beyond the project. W e also
expected , th rough invo lvem ent w ith C M C A , com m unities w ould develop public p rob lem
solv ing skills that cou ld be used to address o ther health and social issues.
D E SIG N
T o assess the effec ts o f the in tervention on youth alcohol access, a lcohol use, and related
p roblem s, w e used a com bination random ized com m unity trial and tim e-series design. T he
random ized com m unity tria l includes seven socially and geograph ically d istinc t upper
m idw estern com m unities random ly assigned to receive the in tervention p rogram , w ith e ight
o thers random ly assigned to serve as contro ls. B aseline surveys w ere conducted in each
com m unity am ong a num ber o f targeted groups and repeated three years later. T he m ultip le
tim e-series design is superim posed on the com m unity tria l such that the sam e ou tcom e
m easures (e.g ., traffic crashes) are co llected from the sam e com m unities, bu t the ou tcom e
variab les are m easured at m any m ore poin ts in tim e bo th p rio r to and after the onse t o f the
in terven tion p rog ram (W agenaar et a l., 1994).
A ll school d istric ts in M inneso ta and w estern W isconsin w ere screened fo r 9 th grade
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enro llm ents o f at least 200, no participation in o ther U niversity o f M inneso ta alcoho l-related
studies, at least 25 m iles in d istance from o ther e lig ib le com m unities, and concen tra tion o f
students in three o r few er m unicipal ju risd ictions. T w enty-four d istric ts that m et these crite ria
w ere iden tified and invited to partic ipate in the study. T o participate, distric t o ffic ials had to
agree to random assignm ent and allow access to 9 th and 12th grade students fo r the baseline
and fo llow -up school surveys. F ifteen o f the 24 elig ib le d istricts agreed to partic ipate in the
study; the m ost com m on reason fo r refusal w as recent partic ipation in ano ther a lcohol-related
survey. T he 15 com m unities had an average population o f 20,836. T here w ere an average 35
“on-sa le” outlets (i.e., take-ou t liquor and grocery stores) and 14 “off-sa le” outlets (i.e ., bars,
taverns and restaurants) in each o f these com m unities.
T he 15 partic ipating d istricts w ere m atched on state, p resence o f a residential co llege o r
university , popu lation size, and on the results o f the baseline alcohol purchase survey. G iven
the odd num ber o f sites, six pairs w ere form ed, along w ith one triplet. O ne site from w ithin
each pair o r trip let w as selected at random for allocation to G roup A and the rem ain ing sites
w ere assigned to G roup B; in th is w ay, the tw o groups w ere structured so as to be sim ilar at
baseline on the m atching factors. O ne o f the tw o groups w as then assigned at random to
becom e the In terven tion G roup; the o ther becam e the C ontrol G roup (W agenaar e t al., 1994).
SO U R C E S O F D A T A A N D ST A T IST IC A L A N A L Y SE S
K ey pre- and post-in terven tion data w ere collected from a variety o f sources, including: (1)
self-adm in istered or in-school surveys o f 9 th and 12th graders, (2) te lephone surveys o f
young adults aged 18 to 20, (3) te lephone surveys o f alcohol outlet ow ners and m anagers, (4)
pseudo-underage alcohol purchase attem pts, (5) analyses o f new spaper coverage o f alcohol
issues, (6) co llection o f archival data on com m unity-level ind icators o f alcohol use and
m isuse, and (7) process evaluation data collected in the in terven tion com m unities by local
com m unity o rganizers. A ll data co llection protocols included approved prov isions fo r the
pro tection o f hum an subjects. T he first four data collection com ponents w ere conducted in
1992 as a baseline, before the com m unity w as organized for action on underage drink ing , and
again in 1995 to m easure any changes that m ay be attributable to the organ izing efforts. D ata
co llection com ponents five through seven con tinued th roughout the baseline and in tervention
phases o f the project. A ll data analyses used m ixed-m odel regression (M urray & W olfinger,
1994), tak ing into account baseline levels in both the in tervention and con tro l groups,
con tro lling fo r a variety o f relevant covariates, and accounting fo r the nesting o f indiv idual
respondents in communities.
F IN D IN G S T O D A T E
T he in tervention phase ended D ecem ber, 1995, data co llection ended m id -1996, and fo llow -
up data are now being analyzed. R esults from baseline and early fo llow -up analyses have
prov ided im portant inform ation on patterns o f alcohol availab ility am ong youth , w here it is
obtained , how it is used, and potential strategies for prevention.
W e sought to increase the p roportion o f alcohol outlets that request age iden tifica tion from
young buyers and decrease the propensity o f outlets to sell to those buyers. A lcohol purchase
attem pts assessed the degree to w hich buyers w ho appeared under the legal age could
purchase alcohol. R esults at baseline show ed that buyers w ere successful in purchasing beer
w ithout age iden tifica tion in 50% o f attem pts in “on-sale” outlets and in 52% o f attem pts in
“off-sa le” outlets (Forster e t al., 1995). In “off-sa le” businesses, buyers w ere m ore successfu l
i f the salesperson w as m ale and if the businesses w ere located in a residential area o r a m all,
“on-sale” purchase attem pts w ere m ore likely to be successful if the server appeared to be
younger than 30 years o ld , if the business w as a restauran t as opposed to a b ar a lone, and if
signs w arn ing against sales to underage persons w ere located a t checkouts. A fter the
com m unity o rganizing in tervention the p roportion o f outlets check ing age iden tifica tion
increased am ong bo th on- and “off-sa le” alcohol outlets, w ith a grea ter increase am ong “off-
sale” outlets, an effec t seen un ifo rm ly across the seven in tervention sites. A lso, the proportion
o f bo th on- and “off-sa le” outlets selling to our confederate buyers decreased (Figure 1).
In addition to testing the propensity o f alcohol outlets to check age iden tifica tion and sell to
young-appearing buyers, practices and policies o f com m ercial outlets in the 15 study
com m unities w ere exam ined v ia te lephone surveys o f ow ners and m anagers (W olfson e t al.,
1996; F igure 2). T he surveys revealed changes potentially resulting from the in tervention .
M erchants w ere asked w hether they check age iden tifica tion fo r all custom ers w ho appear
under age 30. T he proportion responding affirm atively did not change in “on-sale” outlets,
but increased am ong “off-sale” outlets in the in tervention com m unities. W e asked w hether
m erchants had ever been cited fo r sales to m inors. A m ong both on- and “off-sa le” ou tle ts the
in terven tion w as associated w ith an increase in the proportion reporting having been cited,
although the increase am ong “off-sale” outlets w as sm aller. W hile not sta tistically significant
at conventional levels, the effec t w as seen unifo rm ly across the seven in terven tion cities. W e
also assessed m erchan ts’ perceived likelihood o f being cited by law enforcem ent agents if
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they w ere to sell o r serve to m inors. A n ob jective o f the in terven tion w as to deter m erchan ts
from selling to m inors by increasing the perceived chances o f receiv ing an en fo rcem en t
consequence. In both on- and “off-sale” outlets the in tervention resu lted in h igher levels o f
perceived likelihood o f citation. F inally , a m easure o f m erchants care in p reven ting access to
alcohol by m inors is the degree to w hich they refuse sales to a 21 -year-o ld accom pan ied by a
m inor. A t post-test, outle ts in the in tervention com m unities w ere less likely to rep o rt that they
w ould sell in such situations, com pared to the con tro l group.
R esults from baseline surveys o f high school students (n= 10,391) and 18- to 20-year-o lds
(n=3,095) show ed that a person age 21 or over w as the m ost com m on source o f alcohol for
last drink ing occasion , and that direct purchase from a com m ercial ou tle t (e.g ., bar, liquor
store) w as the second m ost prevalen t source fo r those aged 18 to 20 (W agenaar e t al., 1996).
Post-test surveys o f 18- to 20-year-o lds revealed substantial declines due to the in terven tion
in the p roportion o f o lder teenagers w ho tried to buy alcoholic beverages. E igh teen to 20-
year-o lds w ere also less likely to d rink in bars o r taverns after the in tervention , and reported
increased d ifficu lty in getting alcohol from outlets (F igure 3). H igh school sen iors sim ilarly
reported increased d ifficu lty in getting alcohol from outlets after the in tervention .
T he surveys o f 18- to 20-year-o lds found that the in terven tion resu lted in a decline in the
proportion w ho prov ide alcohol to younger teens. In addition, the p roportion o f 18- to 20-
year-o lds w ho drank alcohol in the past 30 days declined, and the num ber o f d rink ing
occasions in the past m onth and the num ber o f d rinks on the last drink ing occasion declined.
T he prevalence o f binge drink ing w as not affected (Figure 3).
T he C M C A project successfully m obilized random ly selected com m unities, im proved the
practices o f alcohol m erchants, and reduced the accessibility o f alcohol to 18- to 20 -year-o lds,
traditionally a d ifficu lt segm ent o f the population to affect. W hile these initial analyses are
im portant, results should be in terpreted cautiously. T here w as a secular trend in o u r contro l
g roup that resu lted in the in tervention versus contro l g roup d ifferences being sm aller than w e
had adequate sta tistical pow er to fully assess. Investigation o f such contextual facto rs and
additional sta tistical analyses are continuing on the C M C A project. N evertheless, resu lts to
date indicate that a com m unity o rganizing approach to changing public po licy and
institu tional p ractices can be useful and effective in reducing risk and creating health ier
com m unities.
F ig u re s 1, 2
F ig ure 1: N et E ffects of the C M C A P ro jec t on A lcoho l
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F ig ure 2: N et E ffects of the C M C A P ro jec t on A lcoho l M erch an ts : S e lf-repo rted P ercep tio n s and B ehav io r
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M erchan ts : O bserved B eh av io r
ID Checking ID CheckingOn-Sale Off-Sale
Buy Rate Off-Sale
F ig 3
F ig u re 3: Net Effects o f the C M C A P ro jec t on 18- to 20 -year-o lds
Bought Provided 30dayAlcohol Alcohol DfinlgngFor Last lo Youth Prevalence Drinking Occasion
f of Drinking • of Drinks BingeOccasions on Las) Drinking
in Last Occasion Prevalencemonth
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Occasion in Barrtavem
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R E F E R E N C E S
F orster J.L ., M urray D .M ., W olfson M ., W agenaar A.C. C om m ercial availability o f alcohol
to young people in the upper m idw est: R esult o f alcohol purchase attem pts. Prev Med,
24:342-347, 1995.
M urray, D .M ., W olfinger, R .D . A nalysis issues in the evaluation o f com m unity trials:
P rogress tow ard solu tions in SA S/STA T M IX ED . J Comm Psychol, C SA P S pecial Issue,
140-154, 1994.
W agenaar, A .C ., M urray , D .M ., W olfson, M ., Forster, J.L ., F innegan, J.R . C om m unities
m obiliz ing fo r change on alcohol: D esign o f a random ized com m unity trial. J Comm Psych
(C SA P Special Issue):79-101 , 1994.
W agenaar, A .C ., T oom ey, T .L ., M urray, D .M ., Short, B .J., W olfson, M ., Jones-W ebb, R.
Sources o f alcohol fo r underage drinkers. J Stud Alcohol, 57(3):325-333 , 1996
W olfson, M ., T oom ey, T ., Forster, J.L , W agenaar, A .C ., M cG overn , P .G ., Perry , C .L .
C haracteristics, policies, and practices o f alcohol outlets and sales to underage persons. J Stud
Alcohol, 57(6), 670-674 , 1996.
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